Method and system for testing polymer concentration for oil displacement

Abstract

The application provides a test method and system for polymer concentration for oil displacement, and the test method comprises the following steps: preparing a polymer standard solution, crushing and filtering the polymer standard solution, drawing a polymer standard curve by using gel chromatography, shearing and crushing injection liquid and mother liquor samples, filtering the injection liquid and the mother liquor samples by using a filter membrane, testing by using gel chromatography, comparing the standard curve, and obtaining the concentration of the polymer, filtering produced liquid samples directly by using a filter membrane, testing by using gel chromatography, comparing the standard curve, and obtaining the concentration of the polymer. The test method is simple and easy to operate, and the detection efficiency and accuracy of the polymer concentration are improved.

Description

Technical Field

[0001] This invention relates to the field of chemical flooding for enhanced oil recovery in oil and gas field development, and particularly to a method and system for testing the concentration of polymers used in oil displacement. Background Technology

[0002] In the field of oil and gas field development, polymer flooding has a good effect on enhancing oil recovery. Polymer concentration measurement is a fundamental issue in chemical flooding technology. During all chemical flooding operations, dynamic monitoring of the injected polymer and produced fluids is necessary to understand the oil displacement dynamics. The polymer concentration of the injected fluid is an important indicator in polymer flooding, used to determine whether the injection volume meets design requirements. The polymer concentration of the produced fluid is also an important indicator in polymer flooding, providing data support for judging polymer breakthrough time and recovery extent.

[0003] Currently, methods for detecting polymer concentration include the starch-cadmium iodide method, turbidimetric method, ultraviolet spectroscopy, ultrafiltration concentration and membrane drying method, chemiluminescence nitrogen determination method, viscosity method, and precipitation method. The polymer molecular weight, water sample color, polymer shear, polymer hydrolysis, and mineralization all affect the polymer concentration determination results. Gel chromatography utilizes the fact that gel molecules have internal pores, and after being packed into a chromatographic column, there are also pores between molecules that are larger than the intramolecular pore size. During separation, large molecules pass directly through the pores between gel molecules, resulting in a shorter time and faster exit; while small molecules pass through the intramolecular pores, requiring a longer path and longer exit, thus achieving separation. With national environmental protection and energy conservation requirements, polymer flooding above-ground equipment is becoming more skid-mounted, reducing above-ground construction. To meet design requirements, polymer injection concentrations have increased, currently reaching a maximum of 18000 mg / L. Directly testing the injection concentration of high-concentration polymers remains a significant challenge. Furthermore, as the scale of polymer flooding expands, the types of polymers also diversify, including heat-resistant and salt-resistant polymers, hydrolysis-resistant polymers, microencapsulated polymers, microsphere polymers, etc. These polymers have different structures, and there is no unified and simple method for testing their concentrations. Therefore, it is very important to find a unified, simple method that can test high concentrations of polymers.

[0004] Chinese patent application CN201810028788.5 discloses a method for detecting the concentration of partially hydrolyzed polyacrylamide polymers suitable for offshore oil fields. This method includes sequentially determining the total nitrogen value and ammonia nitrogen value of the sample, calculating the apparent polymer nitrogen value of the sample using the following formula, calculating the actual polymer nitrogen value of the sample using the following formula, and determining the polymer concentration in the sample based on a standard curve. This method fully considers and removes various interfering factors, and based on the linear relationship between polymer concentration and polymer nitrogen value, achieves the purpose of detecting polymer concentration by measuring the polymer nitrogen value.

[0005] Chinese patent application CN201610892294.2 discloses a method for detecting polymer concentration in a sample. The method includes filtering the sample through a filter membrane with a pore size of [insert pore size here]. The filtered material is mixed with an organic solvent for extraction and separation. The aqueous phase is then removed and dialyzed to remove small molecules from the aqueous phase. The dried dialyzed product is weighed and the polymer concentration is calculated.

[0006] Chinese patent application CN202110062600.0 discloses a method for detecting polymer concentration. When determining the polymer concentration in a test solution, only hydrochloric acid and a metal ion crosslinking agent solution need to be added to the test solution. Therefore, when determining the polymer concentration, only the preparation of hydrochloric acid and metal ion crosslinking agent solution is required, which shortens the time spent preparing the solution and improves the detection efficiency of polymer concentration. Summary of the Invention

[0007] In view of the above problems, the present invention is proposed to provide a method and system for testing the concentration of polymers used for oil displacement that overcomes or at least partially solves the above problems.

[0008] According to one aspect of the present invention, a method for testing the concentration of a polymer for oil displacement is provided, the method comprising:

[0009] Prepare a polymer standard solution, break and filter the polymer standard solution, and plot a polymer standard curve using gel chromatography;

[0010] The injection solution and mother liquor samples were sheared and broken up, filtered through a filter membrane, and the polymer concentration was obtained by gel chromatography and compared with a standard curve.

[0011] The extracted fluid sample was directly filtered through a filter membrane, and the polymer concentration was obtained by comparing it with a standard curve using gel chromatography.

[0012] Optionally, the chromatographic column used in the gel chromatography uses isopropanol and carbon tetrachloride with high viscosity to fully disperse the packing material with ultrasound.

[0013] Optionally, the chromatographic column has a specification of 4.6 mm ID × 150 mm and a detection wavelength of 200 nm.

[0014] Optionally, the polymer standard solution has a concentration of 10000 mg / L, and is diluted after being crushed and filtered using a Wu Yin stirrer.

[0015] Optionally, the Wu Yin agitator can be used to break down and filter the material, then dilute it to concentrations of 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 300 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L, or 3000 mg / L.

[0016] Optionally, the shearing and crushing of the injection solution and mother liquor samples specifically includes:

[0017] For samples with concentrations exceeding 7000 mg / L but below 20000 mg / L, use a Wu Yin stirrer at its highest speed for 5 minutes for shearing.

[0018] For samples with concentrations higher than 2000 mg / L but lower than 7000 mg / L, use the Wu Yin stirrer at its highest speed for 3 minutes.

[0019] Polymer solutions with concentrations higher than 1000 mg / L and lower than 2000 mg / L were sheared at the highest speed for 2 minutes using a Wu Yin stirrer.

[0020] Polymer solutions with a concentration below 1000 mg / L were sheared at the highest speed for 1 minute using a Wu Yin stirrer.

[0021] Optionally, the samples after shearing and breaking down the injected liquid and mother liquor are filtered using a 0.45 μm nuclear pore membrane.

[0022] Optionally, the samples of the injection solution and mother liquor, after being sheared and crushed, are diluted to below 3000 mg / L for concentration testing.

[0023] Optionally, the molecular weight after the highest speed shear of the Wu Yin stirrer should be less than 3 million.

[0024] Optionally, the apparent viscosity of the Wu Yin stirrer at room temperature after the highest speed shear is less than 2 mPa·s.

[0025] Optionally, the fitting formula for plotting the polymer standard curve using gel chromatography has a fitting coefficient R² > 0.999.

[0026] This invention also provides a testing system for the concentration of polymers used in oil displacement, applying the above-described method for testing the concentration of polymers used in oil displacement. The testing system includes:

[0027] The standard curve acquisition module is used to prepare polymer standard solutions and obtain polymer standard curves.

[0028] The polymer concentration calculation module is used to obtain the injection solution and mother liquor samples, and to obtain the polymer concentration of the injection solution and mother liquor samples by combining the polymer standard curve;

[0029] The sample polymer concentration calculation module is used to obtain the produced fluid sample and, in conjunction with the polymer standard curve, to obtain the polymer concentration of the produced fluid sample.

[0030] This invention provides a method and system for testing the concentration of polymers used in oil displacement. The method includes: preparing a polymer standard solution; crushing and filtering the polymer standard solution; plotting a polymer standard curve using gel permeation chromatography (GPC); shearing and crushing injection fluid and mother liquor samples, filtering them through a filter membrane, and testing them using GPC, comparing the polymer concentration with the standard curve; and directly filtering produced fluid samples through a filter membrane, testing them using GPC, and comparing the polymer concentration with the standard curve. The testing method is simple and easy to operate, improving the efficiency and accuracy of polymer concentration detection. It has fewer influencing factors, produces high polymer concentrations, and broadens its applicability. The reagents used in the testing method are non-toxic and harmless, making it a green and environmentally friendly method.

[0031] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of a method for testing the concentration of polymers used for oil displacement, provided in an embodiment of the present invention. Detailed Implementation

[0034] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0035] The terms "comprising" and "having," and any variations thereof, in the specification, embodiments, claims, and drawings of this invention are intended to cover non-exclusive inclusion, such as including a series of steps or units.

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0037] In this invention, unless otherwise specified, the preparation method of the polymer standard solution is as follows: Accurately weigh (4 / S) g of sample (S is the solid content), accurate to 0.0001 g. Weigh (200-4 / S) g of preparation water into a 500 mL beaker, turn on the stirrer and slowly add the sample along the vortex wall at (400±20) r / min for 30 s. Stir at a stirring rate of (500±20) r / min for 2 h, and the concentration of the resulting solution is 20000 mg / L. After standing for 24 h, stir slightly with a glass rod and then dilute.

[0038] In this invention, different polymers and preparation water are used as follows: For Class II reservoirs, conventional polymers are used, including partially hydrolyzed polyacrylamide with a molecular weight between 25 million and 30 million, and the prepared water has a salinity of 19334 mg / L; for Class III reservoirs, a temperature- and salt-resistant multi-component copolymer containing amide and AMPS groups has a molecular weight between 30 million and 35 million, and the prepared water has a salinity of 32868 mg / L; for Class V reservoirs, a hydrolysis-resistant polymer containing amide, AMPS, and hydrolysis-resistant groups has a molecular weight between 10 million and 20 million, and the prepared water has a salinity of 44465 mg / L.

[0039] In this invention, the method for testing the solid content of the polymer is as follows: Turn on the power to the constant temperature drying oven and set the drying temperature to 120℃. Place the weighing bottle in the constant temperature drying oven and dry for 2 hours, then place it in a desiccator to cool for 0.5 hours. Weigh the weighing bottle to an accuracy of 0.0001g, and record this as m0. Add approximately 1g of polyacrylamide sample to the weighing bottle, spreading the sample evenly, to an accuracy of 0.0001g, and record this as m1. Place the weighing bottle and sample in a constant temperature drying oven at 120±2℃ and dry for 2 hours, then place it in a desiccator to cool for 0.5 hours. Weigh the total mass of the dried sample and weighing bottle on an electronic balance to an accuracy of 0.0001g, and record this as m2.

[0040] Calculate the solid content according to formula (1):

[0041]

[0042] In the formula:

[0043] S—Solid content, expressed as a percentage (%);

[0044] m0 — Mass of the weighing bottle, in grams (g);

[0045] m1—Total mass of the sample and weighing bottle before drying, in grams (g).

[0046] m2 — Total mass of the dried sample and weighing bottle, in grams (g).

[0047] Example 1

[0048] A method for testing the concentration of polymers used for oil displacement includes the following steps:

[0049] (1) Conventional polymers for Class II reservoirs were prepared with a water salinity of 19334 mg / L.

[0050] (2) Prepare a polymer standard solution of 5000 mg / L with 19334 mg / L water. After shearing at the highest speed for 5 min with a Wu Yin stirrer, test the molecular weight and apparent viscosity. After filtration through a 0.45 μm core pore filter membrane, dilute to 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 300 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L and 3000 mg / L respectively.

[0051] (3) Use gel chromatography to test the standard solution, plot the standard solution curve, and calculate the fitting coefficient R. 2 .

[0052] (4) In the laboratory, polymer solutions with concentrations of 5000 mg / L and 2100 mg / L were prepared using 19334 mg / L water. The solutions were sheared at the highest speed for 3 minutes using a stirrer by Wu Yin. The molecular weight and apparent viscosity after shearing were then tested. The 5000 mg / L polymer solution was diluted 2 times to 2500 mg / L. After filtration through a 0.45 μm nuclear pore membrane, the solutions were tested using gel permeation chromatography, and the concentration was calculated by comparing with a standard curve.

[0053] (5) For Class II reservoirs, polymer mother liquor (field design concentration 5000 mg / L) and injection fluid (field design concentration 2500 mg / L) were taken from the field. The polymer mother liquor and injection fluid were sheared at the highest speed for 3 min using a Wu Yin stirrer. The molecular weight and apparent viscosity after shearing were tested. The polymer mother liquor was diluted 2 times, filtered through a 0.45 μm core-porous filter membrane, and tested by gel chromatography. The concentration was calculated by comparing with the standard curve.

[0054] (6) Polymer produced fluid from Class II oil reservoirs was filtered through a 0.45 μm nuclear pore membrane and tested by gel chromatography. The concentration was calculated by comparing with a standard curve.

[0055] Table 1. Results of polymer concentration tests in Class II reservoirs.

[0056]

[0057] Table 1 shows that the patented invention can accurately measure the concentration of conventional polymers. Comparison with the field mother liquor test results shows that the mother liquor concentration is comparable to the design concentration and is uniformly prepared. Comparison with the wellhead sample test results shows that the concentrations of the injected fluids in both wells are lower than the design concentrations, and the concentrations should be adjusted on-site to ensure uniform mixing. Comparison with the produced fluid test results shows that the polymer concentrations are all low, indicating that the polymer has a good spreading effect in the reservoir.

[0058] Example 2

[0059] A method for testing the concentration of polymers used for oil displacement includes the following steps:

[0060] (1) A temperature-resistant and salt-resistant multi-component copolymer for Class III oil reservoirs, with a water salinity of 32868 mg / L.

[0061] (2) Prepare a polymer standard solution of 5000 mg / L with 32868 mg / L water. After shearing at the highest speed for 5 min with a Wu Yin stirrer, test the molecular weight and apparent viscosity. After filtration through a 0.45 μm core pore filter membrane, dilute to 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 300 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L and 3000 mg / L respectively.

[0062] (3) Use gel chromatography to test the standard solution, plot the standard solution curve, and calculate the fitting coefficient R2.

[0063] (4) In the laboratory, polymer solutions with concentrations of 10000 mg / L and 3000 mg / L were prepared using 32868 mg / L water. The 10000 mg / L polymer solution was sheared at the highest speed for 5 min using a Wu Yin stirrer, and the 3000 mg / L polymer solution was sheared at the highest speed for 3 min using a Wu Yin stirrer. The molecular weight and apparent viscosity after shearing were tested. The 10000 mg / L polymer solution was filtered through a 0.45 μm core-porous membrane and diluted 4 times. The concentration was calculated by comparing with a standard curve using gel permeation chromatography.

[0064] (5) For Class III oil reservoirs, polymer mother liquor (field design concentration 9000 mg / L) and injection fluid (field design concentration 2900 mg / L) were collected from the field. The polymer mother liquor was sheared at the highest speed for 5 min using a Wu Yin stirrer, and the injection fluid was sheared at the highest speed for 3 min using a Wu Yin stirrer. The molecular weight and apparent viscosity after shearing were tested. The polymer mother liquor was filtered through a 0.45 μm core-porous filter membrane and diluted 4 times. The concentration was calculated by comparing with the standard curve using gel permeation chromatography.

[0065] (6) Polymer produced fluid from Class III oil reservoirs was filtered through a 0.45 μm nuclear pore membrane and tested by gel chromatography. The concentration was calculated by comparing with a standard curve.

[0066] Table 2. Results of polymer concentration tests in Class III oil reservoirs

[0067]

[0068]

[0069] Table 2 shows the test results of known samples, demonstrating that this invention accurately measures the concentration of the temperature- and salt-resistant multi-component copolymer. Comparison of the test results of the mine mother liquor and wellhead injection fluid shows that the concentration is comparable to the design concentration, and the preparation and mixing are uniform. Comparison of the test results of the produced fluid shows that all four wells exhibited varying degrees of polymerization, indicating that polymer flooding has entered the later stages.

[0070] Example 3

[0071] A method for testing the concentration of polymers used for oil displacement includes the following steps:

[0072] (1) Anti-hydrolysis polymer for Class V reservoirs, with a water salinity of 44465 mg / L.

[0073] (2) Prepare a polymer standard solution of 20000 mg / L with 44465 mg / L water. After shearing at the highest speed for 5 min with a Wu Yin stirrer, test the molecular weight and apparent viscosity. After filtration through a 0.45 μm core pore filter membrane, dilute to 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 300 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L and 3000 mg / L respectively.

[0074] (3) Use gel chromatography to test the standard solution, plot the standard solution curve, and calculate the fitting coefficient R2.

[0075] (4) In the laboratory, polymer solutions with concentrations of 15000 mg / L and 2500 mg / L were prepared using 44465 mg / L water. The 15000 mg / L polymer solution was sheared at the highest speed for 5 min using a Wu Yin stirrer, and the 2500 mg / L polymer solution was sheared at the highest speed for 3 min using a Wu Yin stirrer. The molecular weight and apparent viscosity after shearing were tested. The 10000 mg / L polymer solution was filtered through a 0.45 μm core-porous membrane and diluted 6 times. The concentration was calculated by comparing with the standard curve using gel permeation chromatography.

[0076] (5) For Class V oil reservoirs, polymer mother liquor (field design concentration 15000 mg / L) and injection fluid (field design concentration 2200 mg / L) were collected from the field. The polymer mother liquor was sheared at the highest speed for 5 min using a Wu Yin stirrer, and the injection fluid was sheared at the highest speed for 3 min using a Wu Yin stirrer. The molecular weight and apparent viscosity after shearing were tested. The polymer mother liquor was filtered through a 0.45 μm core-porous filter membrane and diluted 6 times. The concentration was calculated by comparing with the standard curve using gel permeation chromatography.

[0077] (6) Polymer produced fluid from Class V oil reservoirs was filtered through a 0.45 μm nuclear pore membrane and tested by gel chromatography. The concentration was calculated by comparing with a standard curve.

[0078] Table 3. Results of polymer concentration tests in Class V oil reservoirs

[0079]

[0080] Table 3 shows that the patented invention can accurately test the concentration of the anti-hydrolysis polymer. Comparison of the test results of the mine mother liquor and the wellhead injection fluid shows that the concentration is comparable to the design concentration, and the preparation and mixing are uniform. Comparison of the test results of the produced fluid shows that no polymer was observed at the mine, and the polymer has a good amplification effect.

[0081] Beneficial effects: The testing method of this invention is simple and easy to operate, improving the efficiency and accuracy of polymer concentration detection. This invention can measure polymer concentration, which is of great significance for on-site quality monitoring of chemical flooding.

[0082] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for testing the concentration of a polymer used for oil displacement, characterized in that, The testing method includes: Prepare polymer standard solutions and obtain polymer standard curves; Obtain injection solution and mother liquor samples, and determine the polymer concentration of the injection solution and mother liquor samples by combining the polymer standard curve; Obtain a sample of the produced fluid and determine the polymer concentration of the sample by combining it with the polymer standard curve.

2. The method for testing the concentration of polymer for oil displacement according to claim 1, characterized in that, The preparation of the polymer standard solution and the acquisition of the polymer standard curve specifically include: preparing the polymer standard solution, breaking and filtering the polymer standard solution, and plotting the polymer standard curve using gel chromatography.

3. The method for testing the concentration of polymer for oil displacement according to claim 1, characterized in that, The specific steps of obtaining the injection solution and mother liquor samples, and determining the polymer concentration of the injection solution and mother liquor samples by combining the polymer standard curve, include: The injected liquid and mother liquor samples were sheared and broken up, filtered through a filter membrane, and the polymer concentration was obtained by gel chromatography and compared with a standard curve.

4. The method for testing the concentration of polymer for oil displacement according to claim 1, characterized in that, The specific steps of obtaining the produced fluid sample and determining the polymer concentration of the produced fluid sample by combining the polymer standard curve include: directly filtering the produced fluid sample with a filter membrane, testing it using gel chromatography, and comparing it with the standard curve to obtain the polymer concentration.

5. The method for testing the concentration of polymer for oil displacement according to claim 2, characterized in that, The chromatographic column used in the gel chromatography employs isopropanol and carbon tetrachloride, with the packing material being fully dispersed by ultrasound.

6. The method for testing the concentration of polymer for oil displacement according to claim 5, characterized in that, The chromatographic column has a specification of 4.6 mm ID × 150 mm and a detection wavelength of 200 nm.

7. The method for testing the concentration of polymer for oil displacement according to claim 1, characterized in that, The polymer standard solution had a concentration of 10000 mg / L and was diluted after being crushed and filtered using a stirrer.

8. The method for testing the concentration of polymer for oil displacement according to claim 7, characterized in that, The concentrations of the Wu Yin agitator were broken down and filtered, and then diluted to 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 300 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L and 3000 mg / L.

9. The method for testing the concentration of a polymer for oil displacement according to claim 3, characterized in that, The specific steps of shearing and breaking up the injected liquid and mother liquor samples include: For samples with concentrations exceeding 7000 mg / L but below 20000 mg / L, use a Wu Yin stirrer at its highest speed for 5 minutes for shearing. For samples with concentrations higher than 2000 mg / L but lower than 7000 mg / L, use the Wu Yin stirrer at its highest speed for 3 minutes. Polymer solutions with concentrations higher than 1000 mg / L and lower than 2000 mg / L were sheared at the highest speed for 2 minutes using a Wu Yin stirrer. Polymer solutions with a concentration below 1000 mg / L were sheared at the highest speed for 1 minute using a Wu Yin stirrer.

10. The method for testing the concentration of a polymer for oil displacement according to claim 3, characterized in that, The samples after shearing and breaking down the injected liquid and mother liquor were filtered using a 0.45 μm nuclear pore membrane.

11. The method for testing the concentration of a polymer for oil displacement according to claim 3, characterized in that, The samples of the injection solution and mother liquor were sheared and crushed, then diluted to below 3000 mg / L for concentration testing.

12. The method for testing the concentration of a polymer for oil displacement according to claim 9, characterized in that, The molecular weight after the highest speed shear of the Wu Yin stirrer must be less than 3 million; A microporous membrane filtration method was established to test the maximum molecular weight of polymers that can pass through a 0.45 μm core pore membrane. Using a filtration ratio device, polymers of different molecular weights were passed through a 0.45μm core-pore filter membrane at a pressure of 0.1MPa. The relative viscosity ratio of the polymers before and after passing through the filter membrane was calculated. A viscosity ratio of 1 indicates that all polymers can pass through the 0.45μm core-pore filter membrane, and it was determined that the molecular weight of the polymer after being broken down was less than 3 million.

13. The method for testing the concentration of a polymer for oil displacement according to claim 9, characterized in that, The apparent viscosity of the Wu Yin stirrer at room temperature after the highest speed shear is less than 2 mPa·s.

14. The method for testing the concentration of a polymer for oil displacement according to claim 2, characterized in that, The fitting formula for the polymer standard curve plotted using gel chromatography has a fitting coefficient R² > 0.

999.

15. A testing system for the concentration of polymers used in oil displacement, employing the testing method for the concentration of polymers used in oil displacement as described in any one of claims 1-14, characterized in that, The testing system includes: The standard curve acquisition module is used to prepare polymer standard solutions and obtain polymer standard curves. The polymer concentration calculation module is used to obtain the injection solution and mother liquor samples, and to obtain the polymer concentration of the injection solution and mother liquor samples by combining the polymer standard curve; The sample polymer concentration calculation module is used to obtain the produced fluid sample and, in conjunction with the polymer standard curve, to obtain the polymer concentration of the produced fluid sample.

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